Radio antenna



FIG. 1 is a top, front, and left side perspective view of a radio antenna, showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a left side elevational view thereof; and,

FIG. 7 is a right side elevational view thereof. 

The ornamental design for the radio antenna, as shown and described. 